iMovie 08

OK...so I'm really green at this video stuff and I recently purchased a Panasonic Lumix DMC-FZ35 that uses AVCHD Lite for video. I have a MacBook with iMovie 08. When I uploaded the video everything seemed to go well but when I play back the clips the video plays back faster than actual (approx 2X) but the audio is fine. Does anyone have any suggestions how to fix?

I have a panasonic zs3 that also uses AVCHD Lite. iMovie 09 can port from the camera direct, but afaik it converts the video to apple intermediate codec, which is lossless but takes up a lot of hard disc space. I've been getting round this by dragging the video files onto my MacBook via a card reader, converting them to QT with Handbrake and then importing into iMovie (I use iMovie HD 06).